Chapter 6 Muscles Flashcards
Biceps Brachii
Supinates forearm, flexes elbom
Brachialis
elbow flexion
Brachioradialis
elbow flexion (weak muscle)
Triceps brachii
extends elbow (antagonist to biceps brachii)
Flexor Carpi
wrist flexion
Extensor carpi
wrist extension
Flexor digitorum
finger flexion
extensor digitorum
finger extension
Gluteus Maximus
Hip extension
Gluteus medius
hip abduction (steadies pelvis when walking)
Ilopsoas
Hip flexion (keeps the upper body from falling backwards when standing erect
Hamstring Muscles
thigh extensions and knee flexion
- Biceps Femoris
- Semimembranosus
- Semitendinosus
Saritorius
flexes the thigh
Quadricep Muscles
extends the knee
- rectus femoris
- vastus muscles (lateralis, medialis, intermedius)
Tibialis anterior
dorsiflexion and foot inversion
Extensor digitorum longus
toe extension and dorsiflexion of the foot
Fibularis muscles
plantar flexion and foot eversion
Soleus
plantar flexion
Frontalis
raises eyebrows
orbiularis oculi
closes eyes, squints, blinks, winks
orbicularis oris
closes mouth and protrudes the lips (smooches)
buccinator
flattens the cheek, chews
Zygomaticus
raises corners of the mouth
Masseter
closes the jaw and elevates mandible; chews
Temporalis
synergist of the masseter, closes jaw; chews.
Platysma
pulls the corners of the mouth inferiorly (frown)
Sternocleidoastoid
flexes the neck, rotates the head
Trapezius
elevates, depresses, adducts, and stabilizes the scapula (posterior)
Latissimus dorsi
extends and adducts the humerus (posterior)
Erector spinae
back extension (posterior)
Quadratus lumborum
flexes the spine laterally (posterior)
Deltoid
arm adduction (posterior)
Muscles that arise from the shoulder girdle and cross the shoulder joint to insert into the humerus
Pectoralis major
Latissimus dorsi
deltoid
Pectoralis major
adducts and flexes the humerus
Intercostal muscles
- eternal intercostals–raise rib cage during inhalation
* Internal intercostals–depress the rib
Rectus abdominis
flexes vertebral column and compresses abdominal contents
external oblique
flex vertebral column; rotate trunk and bend it laterally
internal oblique
flex vertebral column; rotate the trunk and bend it laterally
Transversus abdominis
compresses abdominal contents